If storage is that important, and we can see that really being the case, we'd advise going for the larger storage on the iPhone 5S. The added storage and the extra features make the larger 5S better value all round... as long as your heart's set on an iPhone, that is.
We ended this by asking Siri which handset it thought was the best, and it told us to make our own minds up.
Having used the two together, sat often side by side, it is immediately clear which of the two Apple handsets is superior. Be it the sleeker, more industrial design, the lighter weight or the fancy Touch ID technology, the iPhone 5S beats the 5C every time.
It is a little disappointing that we've had to say this, because the iPhone 5C is, in its own right, a very nice and very capable device. Anybody that has purchased one, or is thinking about purchasing one won't be left disappointed by what the 5C has to offer.
In all, the iPhone 5S brings a lot of features to market that make it more pleasant to use than its lower spec-ed brother. We can't help but feel that the appeal of the 5C is limited, with playground politics meaning that 5S will always bring more appeal - and for the money, there's not a lot of difference in price between the two devices.
However, that doesn't mean that the 5C is without charm. It's got a strong and unique design and does give a lower entry point for an iPhone user. It may be a rebadged iPhone 5, but that's no bad thing. We would always recommend you look at the 5S if you're buying the C, and beseech you to save a little more as the gap between the two is so vast.